CL-JSON-LD

CL-JSON-LD is a library that implements JSON-LD functionality, as described on the JSON-LD website.

Note that this is not the CL-JSON library.

The implementation of this library was inspired by and closely follows the pyld library.

Authors

The library was created by RD Projekt Sp. z o.o. Sp. k. You can reach us at [email protected] or http://www.rdprojekt.pl/.

License

Copyright (c) 2014 RD Projekt Sp. z o.o. Sp. k.

Use is subject to license terms.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Installation

Use cl-json-ld.asd file to install the library.

If you have Quicklisp installed, you can use it to download dependencies automatically:

(push "/path/to/cl-json-ld/" asdf:*central-registry*)
(ql:quickload :cl-json-ld)

Depending on whether you have ST-JSON or Yason installed for JSON handling, one of those will be used. If no library is installed, ST-JSON will be downloaded by Quicklisp.

JSON-LD tests

You can run the JSON-LD test suite by executing:

(asdf:operate 'asdf:test-op :cl-json-ld-tests)

Usage

General notes:

• Whenever a function accepts options, options is a plist.
• JSON objects are objects in our internal format (objects are hashmaps, lists are lists) converted from either ST-JSON or Yason. You can use jsd-read to read them from string or jsd-to-string to write them to string.

The module exports the following functions:

from-rdf (input &optional options)

Converts RDF input into ST-JSON.

If a string is passed as input, it's assumed to be in the "application/nquads" format and converted to the internal dataset format.

The result is a JSON object.

If you want more control over formats, you can use either the register-rdf-parser function or the json-ld-processor class and its methods: processor-from-rdf and processor-register-rdf-parser.

to-rdf (input &optional options)

Converts JSON input into a string (if :format option equals "application/nquads") or to the internal dataset format.

Input can be a URL or a JSON object. You can pass :document-loader in options to use a custom URL loader.

expand (input &optional options)

Performs JSON-LD expansion.

Input can be a URL or a JSON object. You can pass :document-loader in options to use a custom URL loader.

Output is a JSON object.

compact (input ctx &optional options)

Performs JSON-LD compaction.

Input is the same as for the expand function.

Ctx can be a JSON object or a URL.

You can pass :document-loader in options to use a custom URL loader.

Output is a JSON object.

flatten (input ctx &optional options)

Performs JSON-LD flattening.

Input is the same as for the expand function.

Ctx can be a JSON object or a URL.

You can pass :document-loader in options to use a custom URL loader.

Output is a JSON object.

normalize (input &optional options)

Performs JSON-LD normalization.

Input can be a URL or a JSON object.

You can pass :document-loader in options to use a custom URL loader.

Output is a string (if :format option equals "application/nquads") or internal dataset format.

frame (input frame &optional options)

Performs JSON-LD framing.

Frame and input can be URLs or JSON objects.

You can pass :document-loader in options to use a custom URL loader.

Output is a JSON object.

set-document-loader (load-document)

Set load-document function as the default document loader.

get-document-loader ()

Return the default document loader function.

jsd-read (source)

Read a string or stream and return internal JSON representation.

jsd-to-string (element)

Write a JSON element (in internal JSON representation) to string.

jsd-make (args)

Make an internal JSON representation object with keys and values as alternating values of args. Example:

(jsd-make "foo" 3
          "bar" 5)